Thinking of converting from Surge to EOH

[DEcosse]

I was just interested to read that, it hadn't crossed my mind - I would use my Mityvac though - have done countless exchanges with that and it always works great

[bruceb58]

I was just interested to read that, it hadn't crossed my mind - I would use my Mityvac though - have done countless exchanges with that and it always works great

I just follow the instructions for whatever EOH unit I happen to be using. This is for the Titan unit on my Cobalt trailer

Titan_EOH.JPG

The dexter instructions are nearly identical but they tell you to have a second person step on the brake pedal. Dexter also suggests bleeding brakes twice if you are using discs.

Page 10
https://pjtrailers.com/wp-content/uploa ... ec_Hyd.pdf

[mdadgar]

+1 to "no perceptible delay" with EOH brakes.

No way in hell would I go back to surge brakes. What a huge upgrade.

- Mark

[Titaniumboy]

Took me a while and removal of the bleeder before I figured out what was going on! Is it possible @Titaniumboy that there were speed bleeders in the calipers?

I have the UFP Trailer Buddy DB35 disc brake calipers and I think they use just regular bleeder screws. UFP is now part of Dexter Axle.

https://www.dexteraxle.com/product/202 ... it-lh-db35

4398D5D1-61B5-4590-A824-AF97307F2983.png

[Titaniumboy]

I have used vaccum pumps before...PITA as the bleeder screw leaks air around its threads. Just as easy to just pump the surge brake breakaway lever. On my pontoon trailer, I bought an adapter for my Motive brake pressure bleeder to pressurize the master cylinder and do it that way.

I think air leaking around the bleeder screw threads was my nemesis also. Removing the bleeder screw and applying heavy grease to the threads only helped a little.

I looked into the Motive brake bleeder and that is a nifty setup. My only issue is that my surge brake actuator has a rubber cap without any threads on the master cylinder, which is below the plastic disc shown in the picture below. This is not my actual actuator as I just grabbed this photo off of the Internet (mine has almost no rust). My actuator is a GDC (Global Direct Components) GDC80 and it seems to be an orphan as there is virtually no information on the internet.

05E71952-7683-4535-9310-1515FB60B483.jpeg

The Motive brake bleeder would help with a serious issue when I’ve bled my trailer brakes before. The GDC80 actuator brake fluid tank is so small that you only get about two strokes out of the actuator before you run the real risk of the tank running too low and letting air in the system. Ask me how I know this.

What kind of adapter did you need for your boat trailer?

[bruceb58]

I have used vaccum pumps before...PITA as the bleeder screw leaks air around its threads. Just as easy to just pump the surge brake breakaway lever. On my pontoon trailer, I bought an adapter for my Motive brake pressure bleeder to pressurize the master cylinder and do it that way.

I think air leaking around the bleeder screw threads was my nemesis also. Removing the bleeder screw and applying heavy grease to the threads only helped a little.

I looked into the Motive brake bleeder and that is a nifty setup. My only issue is that my surge brake actuator has a rubber cap without any threads on the master cylinder, which is below the plastic disc shown in the picture below. This is not my actual actuator as I just grabbed this photo off of the Internet (mine has almost no rust). My actuator is a GDC (Global Direct Components) GDC80 and it seems to be an orphan as there is virtually no information on the internet.




The Motive brake bleeder would help with a serious issue when I’ve bled my trailer brakes before. The GDC80 actuator brake fluid tank is so small that you only get about two strokes out of the actuator before you run the real risk of the tank running too low and letting air in the system. Ask me how I know this.

What kind of adapter did you need for your boat trailer?

I have this one. Main problem with most surge units is the clearance of the hole to actually get the adapter onto the master cylinder.

https://www.motiveproducts.com/products ... sal-marine

[Titaniumboy]

I wonder if this is the adapter I would need? I’m guessing that a hole was drilled in the rubber stopper and then a barbed fitting was pressed into the stopper hole. I need to measure the diameter of my master cylinder fill hole and how far down it is recessed.

https://www.motiveproducts.com/product ... d778&_ss=r

DFE07BD5-C9B1-4DDE-9B0B-23E2DC47F91B.png

This one looks like it is meant for professional trailer shops as it gets rid of the need to mess around with chains.

https://www.motiveproducts.com/product ... f7a7&_ss=r

51E676F3-5FB0-49DD-BEF5-07B94E12A611.png

[bruceb58]

If you can't get in a screw in adapter, just bleed then the normal way pulling on the breakaway lever. Even with an adapter you still need to pull on the lever slightly anyway.

[Titaniumboy]

If you can't get in a screw in adapter, just bleed then the normal way pulling on the breakaway lever. Even with an adapter you still need to pull on the lever slightly anyway.

We had tried manipulating the breakaway lever to move the hydraulic cylinder, but found that it did not help in bleeding the brakes. We ended up pushing in the surge coupler by using a 2x4 lever. One end was wedged against the pavement and the other end was a couple of feet above the surge coupler. We pulled on the upper end of the wedged 2x4 and it did a decent job of stroking the surge coupler which in turn stroked the hydraulic cylinder.

I’m not following why the hydraulic cylinder needs to be stroked while using a pressure bleeder?

I fear I’ve hijacked this “Surge to EOH” thread? Should I move this conversation into a dedicated “Brake Bleeding for Dummies” thread?

[DEcosse]

My Mityvac is this one - - it works on vacuum at the bleeder vs pressure at the cylinder and includes the auto-fill component for keeping the cylinder full while bleeding - https://www.skf.com/mityvac/products/br ... es/mva6832

I've bled all kinds of things with my Mityvac including my 51 Chevy and motorcycles. Have not done the trailer but don't forsee any issues.

They are a bit spendy, but if you search on Amazon there are 'clones' available for about $60 (that is for complete kit including the vac bleeder and the autofill)
e.g. (& there are other similar even cheaper)

The advantage here is that you don't need a special adapter/seal for the reservoir and don't need to actuate the brakes at all.
The downside is that you do need a compressor to hook up to it.

The other thing to consider would be just to go with SpeedBleeders - they work! Then you just hook up your bottle at one caliper, actuate the surge with a 2 x 4 while keeping an eye on your reservoir at that end. Speedbleeders, the brand name, come with a sealer already on the threads, so you don't get leaks when you open it. Obviously the sealing compound is only an aid to bleeding, not to create the actual seal on the fitting, which is the needle seat. Personally though, I like to be at the bleeder end to still close it towards bottom of the stroke after it is running clear. So a helper is definitely an asset. The mityvac vaccum system is definitely one-person-friendly operation
As I mentioned in earlier post however you can't combine the speed-bleeder with a vacuum bleeder

[Titaniumboy]

Nice Mityvac pump you have there. My handheld Mityvac works great, it was just the damn bleeder screws apparently leaking air? I need to take a gander at that auto-fill feature.

Remember that my surge actuator reservoir is really really small such that I can safely only get two pumps out of the actuator before needing to add more brake fluid. Really a pain.

Is this thread sealant you’re talking about something very thick like a heavy grease, or is it dry like loctite?

[DEcosse]

@Titaniumboy - it's a dry sealant-, indeed very like a pre-coated loctite which has (semi?) cured

[bruceb58]

I’m not following why the hydraulic cylinder needs to be stroked while using a pressure bleeder?

I found that the pressure bleeder couldn't force the fluid past the closed master cylinder. It didn't need to be "stroked"...just opened slightly by moving the break away lever slightly.

[Titaniumboy]

Ok, that makes sense.

[Tuscany]

A warning about EOH brakes that I have learned...

Drums or surge brakes lag behind tow vehicle application, and you can feel them apply. Regular electric brake application is easily felt and adjusted.
EOH brakes are a different animal. They apply so smooth, and apply so seamlessly perfect with your tow vehicle, that you can not feel the difference. It’s very easy to set your trailer brake setting too aggressive.
The result will be worn out trailer tires.

4,000 miles on my trailer, and the tires were just replaced. Totally worn out.